For the sake of a pop riveter and holes saw I'd just buy them, as above, cheap as chips. But as backinblack says don't expect anyone will want to do the job even if you offer to pay. A lot of garages don't seem to want to work on anything you can't put an OBD on or get a days work out of. I've ended up doing quite a bit of plumbing recently for the same reason, no one will come out for a small job.